code: def __iter__(self):
      while True:
          ctx = self.ctx.read()
          (
              th_ctx,
              th_tgt,
              len_ctx,
              context_ctx,
              position_ctx,
              segment_ctx,
              task_ctx,
          ) = self.__get_item_data(ctx)
          yield th_ctx, th_tgt, len_ctx, context_ctx, position_ctx, segment_ctx, task_ctx
  
file_path: DeepKE/example/llm/CPM-Bee/src/cpm_live/training_tasks/ant/pretrain.py
imports: import torch.utils.data
  import random
  import numpy
label_desc: Use image node_id 5 for calling the CPMAntPretrainDataset obj's underlying member method code with example usage: obj.__iter__() without return types